x = 121

l = len(str(x))  # 得到x是几位数


def input(x, l):
    "将x的每个数字读入数组中"
    result = {}
    i = 0  # 计数
    while x > 0:
        result[i] = x % 10
        x = x / 10
        x = int(x)
        i = i + 1
    return result


result = {}
result = input(x, l)


def pai(result, l):
    "将数组中的内容倒序重新排列"
    new_list = {}
    for i in range(len(result)):
        new_list[i] = result[l - 1]
        l = l - 1
    return new_list


new = {}
new = pai(result, l)
if x < 0:
    print("no")

if new == result:
    print("yes")
else:
    print("no")
